[SOLVED] how to reduce noise in matlab

[meliasamad]

hi,

i want to eliminate noise at certain frequency in matlab. anyone can help me??

 

[weetabixharry]

Your question is not clear. Please describe what you want to do in more detail. Do you mean you want to implement a band stop filter?

 

[D.A.(Tony)Stewart]

Obviously it's not Matlab's fault but the programmer.

What you see is the intermodulation of carrier due to aliasing with another 1 rad/s source. The simple solution cancels the interfering signal.

Let me put on my gold tetrahedral hat for mind reading....


Perhaps the method of detecting the input needs an AC signal cancellation circuit or a higher output level from the BODE calculations.

When Aliasing occurs in amplitutude , it is a MIXING effect due to non-linearities or intentional mixing from an amplitude detector.

Full disclosure of the design or block diagram will get you a better answer,.

 

[meliasamad]

hi..
i want to eliminate noise at 0.5 rad/s using low pass filter but i dont how to code it because this system is a state space matrix..

sorry i'm newbie in MATLAB.. thanks in advanced.

 

[weetabixharry]

i want to eliminate noise at 0.5 rad/s using low pass filter but i dont how to code it

An easy way to do this is using Matlab's fir1 function.

The complete Matlab help page, which shows you exactly how to use the function, is here:
https://uk.mathworks.com/help/signal/ref/fir1.html